A nonvolatile semiconductor storage device includes a row decoder which independently controls a plurality of row select line groups. A negative voltage generated by a debooster circuit is applied to individual row select line groups with time shifts. As a result, peaks of erase current can be suppressed, so that consumption current can be reduced. In this device, a current limiting circuit of the booster circuit limits the consumption current of the booster circuit, allowing voltages to be generated within a range under a specified current value according to the conditions of voltage application to the individual row select line groups. Thus, a further reduction of the consumption current at a shorter scale can be achieved.